1. Field of the Invention
This invention pertains generally to mechanical guns and projectors, and more specifically to the magazines used in paintball guns for holding a supply of paintballs. For the purposes of this disclosure, paintball guns are specifically defined as apparatus that propel paint capsules from a barrel in rapid succession and at relatively high speeds. The paintball capsules are designed to break upon impact with an object or person, thereby rendering an identifiable mark, without injuring the person or object.
2. Description of the Related Art
Paintball guns are designed to preferably be capable of firing, in rapid succession, a relatively large number of paintballs in a short period of time. Firing rates in excess of twenty balls per second are readily available on current models. To support the large demand for paintballs that this rapid firing rate creates, a magazine is provided which stores the paintballs until the balls are delivered to the gun firing chamber. Basic paint ball magazines are little more than large hoppers with a feed tube extending therefrom, a sort of closed funnel through which paint balls are dropped into the firing chamber. The maximum size of the magazine is limited generally by the size of the target which is presented to a competitor, and to the gain in weight and loss in mobility which occur with larger magazines.
A common type of magazine in use is illustrated in U.S. Pat. No. 5,282,454 to Bell et al, the contents which are incorporated herein by reference, which discloses a large magazine with sloping ends and side walls that lead downward to a tubular passageway referred to as a feed tube.
Gravitational forces tend to urge the paint balls to the feed tube, as known in the prior art. The magazine is large, capable of holding many paint balls at a time. The feed tube is connected to the firing chamber of the gun, so that as the paint balls are carried through the tube, they are fed into the firing chamber. A similar magazine with novel powered ball delivery is illustrated by Tippman et al in U.S. Pat. No. 5,722,383, the contents which are additionally incorporated herein by reference.
To keep the size of the magazine within reasonable size ranges, refill containers referred to as pods are provided which contain a store of additional paintballs. Standard pods are configured in the shape of a cylinder, and have a spring loaded cover which holds the balls inside. To reload a typical prior art magazine, the participant will open a closure on the magazine, set the gun down or hold the gun under the arm or between the knees, hold the refill pod with one hand, and pivot the spring-loaded cover with the other hand. Only then can the paintballs be transferred from pod to magazine. This type of transfer requires a great deal of time and attention, and yet still almost always results in a spilling of paintballs.
Quite unlike conventional explosive-propelled munitions, paintballs are relatively round and have an exterior formed from a semi-rigid gelatinous compound. The balls must break with applied forces sufficiently small to prevent harm to a person struck by the ball, and the gelatinous compounds have proven to be successful in this application. The gelatinous compound is, however, known to be affected somewhat by such variables as temperature and relative humidity, and may be sufficiently frangible to fail within the magazine on occasion. In such instance, the participant will often be forced to cease use of the gun, and disassemble and clean the magazine. Removal and replacement of the magazine is often relatively difficult, making this a cumbersome two-handed operation that requires the participant's complete attention. In other words, the participant may be competitively disabled and become an easy target for the competition's shots.
Farrell, in U.S. Pat. No. 5,511,333 incorporated herein by reference, illustrates a magazine less prone to breakage, replaceable, and designed not to jam. Unfortunately, the straight tube design severely limits the number of balls contained within a single magazine. When a rapid fire sequence is initiated, the gun may not jam, but it is highly probably that the magazine will empty, still rendering the gun temporarily disabled.
Another method of providing paintballs is proposed by Miller in U.S. Pat. No. 5,097,816, incorporated herein by reference. Therein, a large helical magazine is provided through which the paintballs pass in a single row, eventually leading to the firing chamber. Unfortunately, the Miller design does not use space efficiently, requiring a large helical path with the center portion thereof unused. The extra dimension is undesirable. The large helical path is substantially more difficult to manufacture, adding cost and reducing yield. Furthermore, because of the reduced slope of the surfaces heading into the firing chamber, actual feed rates may be reduced and paint balls may not be provided at speeds sufficient to meet the needs of the more rapidly firing guns. Cleaning of the Miller construction, which is necessary over time to ensure smooth feeding of the paint balls, and which may still be required should a defective or weak ball break, is very difficult also due to the inaccessibility of the central loops of the helix.
Recognizing the need for improved reload capability, U.S. Pat. No. 6,722,355 by Andrews incorporated herein by reference, proposes a custom pod and magazine. In Andrews, the pod has a rotating door that opens when the pod is mated with the magazine, to release paintballs into the magazine. Unfortunately, the Andrews design requires custom components and so does not work with existing magazines and refill pods. Other custom pods and magazines are similarly proposed by U.S. Pat. No. 6,055,975 by Gallagher et al; U.S. Pat. No. 5,809,983 by Stoneking; U.S. Pat. No. 6,234,157 to Parks; published application 2002/0059927 to Woods; U.S. Pat. No. 6,729,321 by Ho; published application 2004/0074488 by Ho et al; and international application WO03087697 by Ho, the contents of each which are incorporated herein by reference for their teachings. As demonstrated by the recent activity, there is a need for improved loading.